The use of Chebyshev cardinal functions for solution of the second‐order one‐dimensional telegraph equation

A numerical technique is presented for the solution of the second order one‐dimensional linear hyperbolic equation. This method uses the Chebyshev cardinal functions. The method consists of expanding the required approximate solution as the elements of Chebyshev cardinal functions. Using the operational matrix of derivative, the problem is reduced to a set of algebraic equations. Some numerical examples are included to demonstrate the validity and applicability of the technique. The method is easy to implement and produces very accurate results. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009     

On the use of lattice Boltzmann model for simulating dean flow of non-Newtonian fluids in curved square ducts

In the present work, the effect of a fluid’s shear-thinning and extension-hardening behavior is investigated on its flow characteristics in a typical curved square duct using a three-dimensional 27-velocities (D3Q27) incompressible lattice Boltzmann model. The main objective of the work is to examine how a fluid’s non-Newtonian viscous behavior affects the onset of Dean instability (i.e., the sudden shift from a two-cell to a four-cell vortex structure) in a curved square duct. The fluid of interest is assumed to obey Pinho’s rheological model in which shear-thinning and extension-hardening are both represented by a single power-law equation. It is found that shear-thinning has a stabilizing effect on the flow. On the other hand, extension-hardening is found to destabilize the flow.     

Preparation of chromium and sulfur single and co-doped TiO2 nanostructures for efficient photoelectrochemical water splitting: effect of aliphatic alcohols on their activity

Journal of Solid State Electrochemistry - Single and co-doped chromium and sulfur TiO2 nanotubes appropriate for photoelectrochemical water splitting application have been prepared and...     

A structural interpretation of the two components governing the kinetic fragility from the example of interpenetrated polymer networks

Kinetic fragility and cooperativity length, two major characteristics of the relaxation dynamics at the glass transition, are, respectively, investigated by dynamic mechanical analysis and modulated temperature differential scanning calorimetry in a series of interpenetrated polymer networks based on acrylate and epoxy systems. The relaxation dynamics are impacted by two variables: the rigidity of the network, and the structural heterogeneity resulting from blending. However, the fragility and the cooperativity do not vary similarly. The glass transition progressively broadens as the mass fractions of acrylate and epoxy become equivalent, leading to a strong decrease in cooperativity. On the other hand, under the same conditions, the fragility transitions between the lower value of pure acrylate and the higher value of pure epoxy. This divergence helps concluding that the variations in the temperature dependence of the relaxation time are not purely related to the more or less cooperative nature of the glass transition. By splitting the fragility index in a volume contribution and an energetic contribution, it is shown that the contribution of cooperativity to the variations of the relaxation time with temperature is increased under two structural conditions: low backbone rigidity and high intermolecular interactions. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1393–1403     

Zitterbewegung in External Magnetic Field: Classic versus Quantum Approach

We investigate variations of the Zitterbewegung frequency of electron due to an external static and uniform magnetic field employing the expectation value quantum approach, and compare our results with the classical model of spinning particles. We demonstrate that these two so far compatible approaches are not in agreement in the presence of an external uniform static magnetic field, in which the classical approach breaks the usual symmetry of free particles and antiparticles states, i.e. it leads to CP violation. Hence, regarding the Zitterbewegung frequency of electron, the classical approach in the presence of an external magnetic field is unlikely to correctly describe the spin of electron, while the quantum approach does, as expected. We also show that the results obtained via the expectation value are in close agreement with the quantum approach of the Heisenberg picture derived in the literature. However, the method we use is capable of being compared with the classical approach regarding the spin aspects. The classical interpretation of spin produced by the altered Zitterbewegung frequency, in the presence of an external magnetic field, are discussed.     

A Turn Off Fluorescence Probe Based on Carbon Dots for Highly Sensitive Detection of BRCA1 Gene in Real Samples and Cellular Imaging

Journal of Fluorescence - In this research, DNA-modified carbon dots (CDs) were exploited to construct a fluorescence assay for breast cancer genes (BRCA1, a potential marker for cancer diagnosis)...     

Synthesis of narrow size distribution sub-micron TiO2 spheres

Ultra-fine spheres of TiO₂ are synthesized through sol-gel colloidal processing. Compared to previous studies, the present work shows a considerable achievement in controlling the shape of the produced particles as well as a relatively narrow size distribution.     

The influence of different factors on the stability and ultrafiltration of emulsified oil in water

The effects of different operating conditions on ultrafiltration (regenerated cellulose with a cut-off of 100 kg/mol) of cutting oil were studied for two different cases. The factors, examined at three levels, included: pH, oil concentration, feed flow velocity, and temperature. The salt (NaCl and CaCl₂) concentration was examined at three levels as well. A lower concentration range was used initially and was increased in the second case.